Bump ch.qos.logback:logback-classic from 1.2.0 to 1.2.13 in /rackspace

Bumps [ch.qos.logback:logback-classic](https://github.com/qos-ch/logback) from 1.2.0 to 1.2.13.
- [Commits](https://github.com/qos-ch/logback/compare/v_1.2.0...v_1.2.13)

---
updated-dependencies:
- dependency-name: ch.qos.logback:logback-classic
  dependency-type: direct:production
...

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